1. Field of the Invention
The present invention relates to a reusable filter unit which can be used, for example, with internal combustion engines, such as diesel or gasoline powered engines, and which provides both a filtering and an additive function. The filter can be used for a variety of fluid media, although the preferred embodiment describes a filter intended for water filtering purposes, used in the engine's cooling system.
2. Background Information
Filters for internal combustion engines having both filtering and additive functions are known in the art. Such filters have a filtering part which might include a paper filter media, and an additive part which would conventionally contain additives which can be used to treat the filtered fluid, such as anti-corrosion or anti-pitting additives.
These prior art dual function filters, however, suffer from a number of drawbacks. They are of a relatively complex construction, consisting of numerous parts, which render them difficult and expensive to manufacture. Also, these dual function filters are not reusable. When the filtering media within the filter become polluted with removed impurities, and/or when the chemical additive is exhausted, the filter must be discarded, or essentially reconstructed. Further, because of the complexity of the prior art units, they must be made largely of metal in order to withstand the constructional forces.
It is an object of this invention to provide a filter for fluids which alleviates the disadvantages of the prior art devices.
Specifically, it is an object of this invention to provide a filter which provides both a filtering and an additive function and which can be reused in that the filtering media and the additive can be replaced easily and conveniently without disassembling or reconstructing the device.
Further, it is an object of this invention to provide a filter which is relatively simple and inexpensive to construct and which is particularly adapted to be constructed of plastic components.